Tool selection system

ABSTRACT

Recorded instructions in a memory include a plurality of tool codes corresponding to tools to be selected and a plurality of corresponding tool addresses. A plurality of tools are stored in a movable tool storage. When a tool code is commanded in a tape, the storage address corresponding to such tool code is read out from the memory and moves the tool storage to a position at which the desired tool may be removed therefrom. The tool storage is halted when the tool address of the desired tool corresponds to the tool address read out from the memory.

United States Patent Inaba et al.

[54] TOOL SELECTION SYSTEM [72] Inventors: Seiuemon lnaba; KengoKobayashi, both 1 of Kawasaki, Japan [73] Assignee: Fujitsu Limited,Kawasaki, Japan [22] Filed: July 15, 1970 21 Appl. No.: 55,148

[30] Foreign Application Priority Data July 23, 1969 Japan ..44/58147[52] [1.8. CI ..318/601, 318/603 [51] ..G05b 19/26 [58] Field of Search..318/601, 602, 603

[56] References Cited UNITED STATES PATENTS.

3,495,775 2/1970 Camillo ..318/601 X [151 3,657,627 [451 Apr. 18, 19723,414,785 12/1968 Orahood et al ..318/603 3,517,286 6/1970 Stobbe.,..3l8/603X Primary Examiner-Benjamin Dobeck Attorney-Curt M. Avery,Arthur E. Wilfond, Herbert L. Lerner and Daniel J. Tick [57] ABSTRACTRecorded instructions in a memory include a plurality of tool codescorresponding to tools to be selected and a plurality of correspondingtool addresses. A plurality of tools are stored in a movable toolstorage. When a tool code is commanded in a tape, the storage addresscorresponding to such tool code is read out from the memory and movesthe tool storage to a position at which the desired tool may be removedtherefrom. The tool storage is halted when the tool address of thedesired tool corresponds to the tool address read out from the memory.

4 Claims, 7 Drawing Figures T001. STORAGE 6 C005 PAATE l4 DETECTOR 15v 1. D/IV IDEA/CE LLQA/ZZMNO ll /Rc u/ 7' 3 4 IE I F/P FL 0P 9 FLIP FLOPPATENTEDAPR 18 1912 v 3, 657, 627

sum u F 4 LlW/MfR/CAL (WK TROLL ER 57 F (0R5 MEMORY 52 l U/V/r 53 MP52540007 1 TOOL 67094 65 61 DEV/CE 54 i l 2 comm/10E am ur-007, 07

cwA IVA/EL 58 59 SW/T'C/IBOARD 56 0L TOOL Z3053 /6465 Abaeess's F l G 77001. STORAGE W 7 00L (0055 58 ADDRESSES 59 AKTUAL 700i ADDRESS 64 TOOLSELECTION SYSTEM DESCRIPTION OF THE INVENTION The invention relates toatool selection system. More particularly, the invention relates to atool selection system for automatically selecting a desired one of aplurality of tools.

I must be provided with a code plate or the like. The second- ;describedtool selection system is inconvenient from the viewpoint of the program,since a tool address is commanded.

- The principal object of the invention is to provide a new and improvedtool selection system. An object of the invention is toprovide a toolselection system which avoids the disadvantages of known types of toolselection systems.

An object of the invention is to provide a tool selection system whichis of simple structure.

-An object of the invention is to provide and selection systemwhicheliminates the need for a code plate for each tool and in which atool code is commanded for the selection of a tool from the toolstorage.

An object of the invention is to provide a tool selection system whereinthe program is considerably simplified.

An object of the invention is to provide a tool selection system whereinthe program'simply designates a tool code for the tool to be selected.-

An object of the invention is to provide a tool selection system whichfunctions with efficiency, effectiveness and reliability.

" In accordance with the invention, a tool selection system comprises amovable tool storage storing a plurality of tools and having a pluralityof tool addresses each for a corresponding'one of the tools. Memorymeans stores a plurality of .tool

' codes and a plurality of corresponding tool addresses. Command meanscoupled to the memory means commands a tool code for a tool to beselected and locates the tool address in the memory means for the toolcode. Tool removing means removes a tool from the tool storage. Toolstorage position indicating means indicates the position of the toolstorage thereby indicating the tool address of the tool in proximitywith the tool removing means. Control means coupled between the toolstorage position indicating means and the memory means and the toolstorage controls the movement of the tool storage to move the tool to beselected into proximity with the tool removing means when the selectedtool address of the memory means coincides with the tool address of thetool storage position indicating means.

The control means comprises a motor coupled to the tool storage formoving the tool storage. Motor driving means drives the motor. Comparingmeans has an input coupled to the memory means, an input coupled to thetool storage position indicating means and an output coupled to themotor driving means.

The memory means is coupled to the motor driving means and controls therotation and direction of rotation of the motor, in one embodiment ofthe invention; The control means halts the rotation of the motor uponcoincidence of the selected tool address of the memory means and thetool address of the tool storage position indicating means.

In another embodiment of the invention, the motor driving means rotatesthe motor continuously and the control means halts the rotation of themotor upon coincidence of the selected tool address of the memory meansand the tool address of the tool storage position indicating means.

In order that the invention may be readily carried into'effect, it willnow be described with reference to the accompanying drawings, wherein:

FIG. 1 is a schematic block diagram of an embodiment of the toolselection system of the invention;

FIG. 2 is a schematic block diagram of the principal part of the systemof FIG. 1;

FIG. 2 is a schematic block diagram illustrating a method of memorizingtool codes;

FIG. 4 is a schematic diagram showing a switchboard for supplying theaddresses of the tool storage and tool codes;

FIG. 5 is a schematic block diagram of another embodiment of the toolselection system of the invention;

FIG. 6 is a schematic block diagram of a numerical controller of storedprogram type which may be utilized in the tool selection system of theinvention; and

FIG. 7 illustrates the correspondence between the tool storage addressesand the tool codes.

In FIG. 1, a command tape 1 has numerical control information or dataand tool codes representing different tools to be used recorded therein.The command tape 1 may comprise, for example, a perforated tape, whereinthe numerical control data and tool codes are punched. A numericalcontroller 2 reads out the data recorded in the command tape 1. Thenumerical controller 2 reads out the tool code commanded by the commandtape 1 and selects or detects an address recorded in said numericalcon-troller corresponding to the read out tool code. The numericalcontroller 2 then transmits the tool address corresponding to the readout tool code to a coincidence circuit 3 via leads 4.

The numerical controller 2 includes a memory wherein the tool codes,representing tools to be selected, and as indicated in the command tape1, and thecorresponding tool addresses are recorded. The tool addressesare those which correspond to the tools stored in a tool storage, fromwhich the selected tool is to be removed.

A tool holder 5 functions to remove a tool from a tool storage 6 whenthe tool storage is rotated to a position wherein the tool to be removedis in operative proximity with said tool holder. The tool holder 5 mayalso be utilized to reinsert a tool in the tool storage 6. The toolstorage 6 is movable or rotatable under the control of a motor 7 whichis coupled to and drives said tool storage. The motor 7 is driven by amotor driving circuit 8 which drives the motor 7 in either a forwarddirection or a reverse direction.

The coincidence circuit 3 has an output connected to the reset input ofeach of a pair of flip flops 9 and 11. The numerical controller 2 hasinputs connected to the set inputs of the flip flops 9 and 11 via leadsl2 and 13, respectively. The set output of each of the flip flops 9 and11 is connected to an input of the motor driving circuit 8. When thereis a signal in the set output of the flip flop 9, the motor drivingcircuit-8 drives the motor 7 ina forward direction, thereby rotating thetool storage 6 in a forward direction. When there is a signal in the setoutput of the flip flop 11, the motor driving circuit 8 I drives themotor 7 in a reverse direction, thereby rotating the tool storage 6 in areverse direction.

The actual address of the tool in proximity with the tool holder 5 issupplied to inputs of the coincidence circuit 3. There are n toolstorage positions in the tool storage 6. Each of the n tool storagepositions has a numerical value designated by a tool storage address ortool address provided at the circumference of the tool storage 6. A codeplate 14 is mounted on the shaft of rotation of the tool storage 6 sothat said code plate rotates with said tool storage. The code plate 14has a code corresponding to the tool storage addresses recorded thereon.A detector 15 reads out the code recorded on the code plate 14 andtransmits to the coincidence circuit 3 the code corresponding to thetool storage address of each tool in the tool storage 6 as it passes inproximity with the tool holder 5.

When a command in the command tape 1 commands the selection of a tool,the numerical controller 2 reads out the tool code of the tool to beselected. The numerical controller 2 then selects the tool addresscorresponding to the tool code of the tool to be selected and transmitssaid tool address to the coincidence circuit 3. The coincidence circuit3 then compares the tool address of the tool to be selected with thetool address of each tool stored at the tool storage 6 as said toolstorage rotates past the tool holder 5. As each tool moves intoproximity with the tool holder 5, its too] address is transmitted to thecoincidence circuit 3. The coincidence circuit 3 directs the motordriving circuit 8 to rotate the tool storage 6, via the motor 7, ineither forward direction or reverse direction, as long as there is nocoincidence between the tool address of the tool to be selected and thetool address of the tool in operative proximity with the tool holder 5.

When the coincidence circuit 3 determines coincidence between the tooladdress of the tool to be selected, as received from the numericalcontroller 2, and the tool address of the tool in proximity with thetool holder 5, said coincidence cirmotor 7 is deenergized via the motordriving circuit 8.

When the tool storage 6 is halted, and the desired tool is in proximitywith the tool holder 5, said desired tool is removed from the toolstorage 6 by the tool holder 5, under the control of a tool movingcircuit 16, which comprises a known circuit, and which functions in aknown manner, to control the removal of a tool from the tool storage andto control the insertion of a tool into'the tool storage.

FIG. 2 is an embodiment of a circuit for detecting the tool storageaddress corresponding to the tool code recorded in the command tape 1.The correspondence between tool code and tool addresses is recorded ormemorized, prior to the operation of the tool selection system, in ashift register 17. The shift register 17 comprises a plurality ofregister parts of a number equal to the number of tool addresses. Thatis, there are n register parts in the shift register 17. The registerparts of the shift register 17 are interconnected. Each of the registerparts comprises, for example, a bit tool code.

The tool code such as, for example, 10111, recorded in the first address1 is shifted to the second address 2. each time a pulse is supplied tothe shift register 17 from a shift pulse oscillator 18 having an outputconnected to an input of said shift register. The tool code of the n'address n such as, for example, 010] l, is shifted to the first address1 of the shift register 17 and is supplied to a coincidence circuit 19.

If a tool code is commanded by a command tape 21, the commanded toolcode is set in a register 22, having an input connected to a tapereadout (not shown in FIG. 2). The register 22 transmits a numericalvalue to an input of the coincidence circuit 19. Consequently, a searchstart signal SS is provided at each of a pair of input terminals 23 and24. The search start signal SS supplied to the input terminal 23 sets aflip flop 25. The set input of the flip flop 25 is connected to theinput terminal 23 and the set output of said flip-flop is connected tothe input of the shift pulse oscillator 18. When the flip flop 25 isset, its output signal operates the shift pulse oscillator 18, and saidoscillator supplies a shift pulse to the put signal, which is suppliedto the reset input of the flip flop .25. The signal supplied to thereset input of the flip flop 25 resets said flip flop and deenergizesthe shift pulse oscillator 18, so that shifting of the shift register 17is halted. The shifts of the shift register 17 are counted in an addresscounter 26.

The address counter 26 has a counting capacity of n. Thus, by adjustingthe initial condition of the shift register 17 and the initial conditionof the address counter 26, a numerical value of a tool addresscorresponding to the commanded tool code may be expressed in saidaddress counter.

The shift of the shift register 17 is supplied to the address counter 26via a lead 27 connected to the output of the shift pulse oscillator 18.

The content of the address counter 26 is transmitted to an input of adifierence detecting circuit 28 and to an input of a counter memory 29.The content of the address counter 26 is transmitted to the countermemory 29 via AND gates 31 and 32, under the control of the search startsignal supplied via the input terminal 24. The content of the addresscounter 26 is transmitted to the counter memory 29 prior to the supplyof the search start signal SS. When the search start signal SS isprovided, the actual tool address of the tool storage is stored in thecounter memory 29 and the tool address corresponding to the commandedtool code is stored in the address counter 26.

The output of the counter memory 29 is connected to another input of thedifference detecting circuit 28. In order to increase the speed ofselection of the desired tool, the difference detecting circuit 28detects the difierence between the commanded tool address and the actualtool address and transmits a command in a lead 33 or 34. A command inthe lead 33 actuates the motor driving circuit to rotate the motor in aforward direction and a command in the lead 34 actuates said motordriving circuit to rotate the motor in a reverse direction. The contentof the address counter 26 is transmitted to the coincidence circuit 3 ofthe embodiment of FIG. 1.

FIG. 3 illustrates a method of recording the relation between tool codesand tool addresses, wherein the tool codes are stored in a memorycircuit comprising a shift register 35. FIG. 4 is an illustration of aswitchboard for providing an input. In the switchboard, an addressswitch 36 commands tool addresses and a tool code switch 37 sets toolcodes. The switchboard includes a push button switch 38. When the pushbutton switch 38 is depressed, after the address switch 36 and the toolcode switch 37 are set, a tool code designated by said tool code switchis recorded or memorized in the address position designated by saidaddress switch in the shift register 35 of FIG. 3.

In FIG. 3 each bit or component of the shift register 35 comprises awell known two input flip flop. If the address switch 36 is connected toan input terminal n, and the tool code switch 37 is closed in accordancewith the tool code, tool codes are transmitted to a plurality of flipflops f1 to f5 corresponding to the tool address n. When the push buttonswitch 38 of the switchboard shown in FIG. 4 is depressed, the flipflops f1 to f5 are triggered and set the code input. The tool codes forthe other tool addresses 1, 2, 3, n-l are recorded in the same manner asdescribed for the address n.

In the embodiment of FIG. 5, the shift register and the tool storage areshifted in synchronism with each other until the tool code correspondingto the commanded tool code is detected. When the tool code of the toolstorage coincides with the commanded tool code, the movement or rotationof the tool storage is halted. In the embodiment of FIG. 5, a toolstorage 39 is continuously rotated by a motor 41 coupled thereto. Themotor 41 is driven by a motor driving circuit 42. A pulse generator 43is affixed to the shaft of the tool storage 39 and rotates insynchronism therewith.

The pulse generator 43 transmits a pulse each time a tool stored inthe-tool storage 39 passes in proximity with a tool holder of the typedescribed with reference to FIG. 1, and not shown in FIG. 5 .The pulsegenerator 43 may comprise, for example, a rotatably mounted plate ofnon-magnetic material having areas of magnetic material equidistantlyspaced from each other around said plate. A proximity switch 44 ispositioned in operative proximity with the rotating plate of the pulsegenerator 43 and produces a signal or pulse each time a magnetized areapasses in close proximity therewith. The output signals of the proximityswitch 44 are transmitted to a shift pulse oscillator 45.

Each time a pulse or signal is supplied to the shift pulse oscillator 45from the proximity switch 44, a shift register 46 is shifted by onestep. The output of the shift pulse oscillator 45 is connected to aninput of the shift register 46. When the tool command from a commandtape 47 coincides with the tool code shifted out from the shift register46, a coincidence circuit 48 halts the operation of the motor 41 via themotor driving circuit 42. The output of the coincidence circuit 48 isconnected to the input of the motor driving circuit 42. The output ofthe shift register 46 is connected to an input of the coincidencecircuit 48. The read out tool code from the tape 47, read out by asuitable device, not shown in FIG. 5, is supplied to a register 49,having an input connected to the readout device and an output connectedto the other input of the coincidence circuit 48.

FIG. 6 illustrates a numerical controller of the stored program typewhich may be utilized in the tool selection system of the invention. InFIG. 6, a numerical controller 51 comprises a numerical controller ofstored program type. The numerical controller 51 comprises a core memory52, a central processing unit 53, a tape readout device 54, aninput-output channel 55 and a switchboard 56. The output of the corememory 52 is connected to the input of the central processing unit 53.The output of the central processing unit is connected to an input ofthe input-output channel 55. The output of the tape readout device 54 isconnected to an input of the inputoutput channel 55. The output of theswitchboard 56 is connected to an input of the input-output channel 55.

The input of the tape readout device 54 is in operative proximity with acommand tape 57. An input 58 to the switchboard 56 supplies tool codesthereto, An input 59 to the switchboard 56 supplies tool storageaddresses thereto. The input-output channel 55 transfers informations ordata between the central processing unit 53 and the tape readout device54, and the switchboard 56. The data transferred via the input-outputchannel 55 is transmitted to a tool storage 61 via a pair of leads 62and 63.

The core memory 52 of the numerical controller 51 records or memorizes atable as shown in FIG. 7. The table of FIG. 7 indicates the relationbetween the tool storage addresses 59 of the tool storage and the toolcodes 58 corresponding to such addresses. If the code of a tool to beselected is commanded by the command tape 57, via the tape readoutdevice 54, the tool address corresponding to the commanded tool code isdetermined by a search or scanning procedure and the numerical value ofthe tool address is transmitted to the tool storage 61.

The actual tool address 64, which indicates the instantaneous positionof the tool storage 61, by indicating the tool address of the tool thenin proximity with the tool holder (not shown in FIG. 6), is alsorecorded in the core memory 52. The actual tool address is compared withthe tool address in which the tool to be selected was previously locatedto determine whether the tool storage 61 should be rotated in a forwarddirection or a reverse direction. An output signal indicating thedirection of rotation of the tool storage 61 is transmitted to said toolstorage via the lead 63.

The tool storage 61 is rotated by the signal transmitted thereto via thelead 63 from the input-output channel 55 of the numerical controller 51.The The output signal from the accessory code disc (not shown in FIG.6), coupled to and rotatable with the tool storage 61, is compared withthe selected tool address. If the signal from the accessory code disccoincides with the tool address, the rotation of the tool storage 61 ishalted and the desired tool is removed by the tool holder. The tool codedata 58 and the tool storage address data 59 are recorded in the corememory 52 prior to operation of the switchboard 56.

It is possible to modify the tool selection system of FIG. 6 in a mannerwhereby the tool storage does not include a tool storage address and thetool codes recorded in the core memory 52 of the numerical controller 51are checked in synchromsm with the rotation of said tool storage. Thetool storage is then halted and the desired tool is removed, when a toolcode coinciding with the code recorded on the command tape is detected.In such a modification, it is necessary to replace the core memory 52 bysuitable flip flop or the like.

While the invention has been described by means of specific examples andin specific embodiments, we do not wish to be limited thereto, forobvious modifications will occur to those skilled in the art withoutdeparting from the spirit and scope of the invention.

We claim:

1. A tool selection system, comprising a movable tool storage storing aplurality of tools and having a plurality of tool addresses each for acorresponding one of said tools, each of said tools having acorresponding tool code and being free from tool code elements;

memory means storing each of the tool codes and each of a plurality oftool addresses corresponding to each of the codes; command means coupledto said memory means for commanding a tool code for a tool to beselected and locating the tool address in said memory means for saidtool code;

tool removing means for removing a tool from said tool storage;

tool storage position indicating means for indicating the position ofsaid tool storage thereby indicating the tool address of the tool inproximity with said tool removing means; and

control means coupled between said tool storage position indicatingmeans and said memory means and said tool storage for controlling themovement of said tool storage to move the tool to be selected intoproximity with said tool removing means when the selected tool addressof said memory means coincides with the tool address of said toolstorage position indicating means.

2. A tool selection system as claimed in claim 1, wherein said controlmeans comprises a motor coupled to said tool storage for moving saidtool storage, motor driving means for driving said motor and comparingmeans having an input coupled to said memory means, an input coupled tosaid tool storage position indicating means and an output coupled tosaid motor driving means.

3. A tool selection system as claimed in claim 2, wherein said memorymeans is coupled to said motor driving means andcontrols the rotationand direction of rotation of said motor and said control means halts therotation of said motor upon coincidence of the selected tool address ofsaid memory means and the tool address of said tool storage positionindicating means.

4. A tool selection system as claimed in claim 2, wherein said motordriving means rotates said motor continuously and said control meanshalts the rotation of said motor upon coincidence of the selected tooladdress of said memory means and the tool address of said tool storageposition indicating means.

1. A tool selection system, comprising a movable tool storage storing aplurality of tools and having a plurality of tool addresses each for acorresponding one of said tools, each of said tools having acorresponding tool code and being free from tool code elements; memorymeans storing each of the tool codes and each of a plurality of tooladdresses corresponding to each of the codes; command means coupled tosaid memory means for commanding a tool code for a tool to be selectedand locating the tool address in said memory means for said tool code;tool removing means for removing a tool from said tool storage; toolstorage position indicating means for indicating the position of saidtool storage thereby indicating the tool address of the tool inproximity with said tool removing means; and control means coupledbetween said tool storage position indicating means and said memorymeans and said tool storage for controlling the movement of said toolstorage to move the tool to be selected into proximity with said toolremoving means when the selected tool address of said memory meanscoincides wIth the tool address of said tool storage position indicatingmeans.
 2. A tool selection system as claimed in claim 1, wherein saidcontrol means comprises a motor coupled to said tool storage for movingsaid tool storage, motor driving means for driving said motor andcomparing means having an input coupled to said memory means, an inputcoupled to said tool storage position indicating means and an outputcoupled to said motor driving means.
 3. A tool selection system asclaimed in claim 2, wherein said memory means is coupled to said motordriving means and controls the rotation and direction of rotation ofsaid motor and said control means halts the rotation of said motor uponcoincidence of the selected tool address of said memory means and thetool address of said tool storage position indicating means.
 4. A toolselection system as claimed in claim 2, wherein said motor driving meansrotates said motor continuously and said control means halts therotation of said motor upon coincidence of the selected tool address ofsaid memory means and the tool address of said tool storage positionindicating means.